Same problem for me, and the replacement plugin above also provided the fix. Thank you.
I have now resolved this. The problem was due to the WordPress Access Control plugin. I am now restricting menu access via the PublishPress Capabilities plugin (Capabilities>Nav Menus etc) and everything is working fine 🙂
.. and this may be related .. again when logged in on the dektop, the submenu “V” icon is not displayed, although the submenus still appear in this mode
panic over.
I was able to upload a fresh copy of the plugin via FTP and all logins have been restored.
phew.
I have also been able to configure things as I need – at least for now.
regards
Jeremy